<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    span {
      display: inline-block;
      width: 50px;
      text-align: right;
    }
  </style>
</head>

<body>

  <div id="app">
    <span>姓：</span><input type="text" v-model="xing"><br><br>
    <span>名：</span><input type="text" v-model="ming"><br><br>
    <span>姓名：</span><input type="text" :value="fullName"><br />
  </div>
  <script src="./js/vue-2.7.14.js"></script>
  <script>
    const app = new Vue({
      el: '#app',
      data: {
        xing: '尼古拉斯',
        ming: '赵四'
      },
      computed: {
        // fullName() {
        //   return this.xing + '·' + this.ming
        // }

        fullName: {
          get() {
            return this.xing + '·' + this.ming
          },
          set() {

          }
        }
      }
    })
  </script>
</body>

</html>